JPH07211868A - Semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a semiconductor device whose function can be changed even after packaging or mounting. [Structure] Function selection block 3 connected to external terminal 2
Information is written in the non-volatile element inside, and only the block having the required function is activated from the internal functional blocks 4a and 4b by the written information to realize the intended function. The write control terminal 1 is connected to the function selection block 3 and controls the write operation of the nonvolatile element in the function selection block 3 that controls the exchange of information between the external terminal 2 and the function blocks 4a and 4b. Function selection block 3
Are connected to the functional blocks 4a and 4b, and activate one of the functional blocks by the data of the nonvolatile element. When the functional blocks 4a and 4b mutually substitute other functional blocks, the respective functional blocks 4a and 4b
It is possible to repair the defect b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and is suitable for a product in which it is effective to change the function of the circuit after the wiring process, such as a memory having a redundant circuit, and particularly after packaging or mounting. This is suitable when the fuse cannot be blown by a laser as in the case.

[0002]

2. Description of the Related Art Conventionally, a change in the function of a semiconductor device has been realized by changing a mask for wiring in a wiring process as seen in products such as gate arrays.

Further, in a semiconductor memory device, a redundant circuit which replaces a defective portion in an original memory array area and repairs it is activated by cutting a fuse with a laser or the like irradiated from the outside of the semiconductor memory. .

Regarding modification of the function of the semiconductor device,
For example, Ohmsha Co., Ltd., November 30, 1984
Japan, 1st edition, 1st edition, published by The Institute of Electrical Communication of Japan "LSI
Techniques disclosed in documents such as "Handbook" P383 to P385 are known.

[0005]

In the above-mentioned prior art, the functions of the semiconductor device and the semiconductor memory cannot be changed after packaging or mounting for sealing the semiconductor memory. For example, in a semiconductor memory, a defective bit that becomes apparent after packaging cannot be replaced with a redundant bit by using a redundant circuit. Therefore, after packaging, the product must be discarded, and after mounting on a substrate or the like, complicated work such as removing the defective semiconductor device from the substrate is essential.

An object of the present invention is to provide a semiconductor device whose function can be changed even after packaging or mounting.

Another object of the present invention is to provide a semiconductor device capable of improving the product yield by relieving a defective portion after packaging or mounting.

Still another object of the present invention is to provide a semiconductor device capable of greatly simplifying maintenance work.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

That is, the semiconductor device of the present invention comprises a non-volatile storage means for changing the internal electrical connection state by an electric signal from an external terminal.

Further, the semiconductor device of the present invention is connected to a plurality of functional blocks and an external terminal provided commonly or independently to the functional blocks, and the non-volatile storage means in which the control information is written via the external terminals. And a control means for activating an arbitrary functional block among a plurality of functional blocks by the control information of the non-volatile storage means.

Also, in the semiconductor device of the present invention, a plurality of functional blocks are constituted by a main memory section and a redundant memory section capable of substituting at least part of the functions of the main memory section, and the external terminals are the main terminals. The nonvolatile memory means stores the control information input from the address terminal, and the control means is written in the nonvolatile memory means. The redundant memory unit is activated based on the control information.

In the semiconductor device of the present invention, a part of the external terminals is made to function as a control terminal for controlling the writing of information to the nonvolatile storage means via the external terminal.

Further, in the semiconductor device of the present invention, the non-volatile memory means is composed of a non-volatile memory element.

Further, in the semiconductor device of the present invention, the nonvolatile memory means is composed of an electric fuse whose state is permanently changed by the input of an electric signal from an external terminal.

Further, in the semiconductor device of the present invention, the non-volatile storage means is composed of a MOS transistor, and the information inputted from the external terminal is stored by utilizing the shift of the threshold voltage due to the injection of hot carriers. It is a thing.

[0018]

In the semiconductor device of the present invention described above, information is written in the non-volatile storage means connected to the external terminal, and only the block having a required function is activated from the plurality of internal functional blocks by the written information. And realize the desired function. Since the function is changed by writing information through the external terminal, it is possible to change the function regardless of whether the semiconductor device is sealed before or after sealing, or even when mounted in a desired system.

It should be noted that the external terminal referred to here naturally includes, for example, a test pad in a probe inspection in a wafer state, and as a part of the probe inspection, a function change or correction of a found defect is applied to the test pad. Performing in-situ by applying an electrical signal through the probe in contact is also included in the invention.

Further, when the function change is a remedy by substituting a functional defect, the defect can be relieved at an arbitrary time after manufacturing, and the product yield is improved.

Further, after mounting the semiconductor device, it is not necessary to remove the semiconductor device from the substrate, and defect relief and repair can be performed by a function substitution measure by giving a desired signal from an external terminal in the mounted state. Yes, maintenance work is greatly simplified.

For example, when the semiconductor device is a semiconductor memory, a nonvolatile memory means is connected to the address terminal, the address of the defective bit is stored in the nonvolatile memory means, and the defective bit is replaced with the bit of the redundant memory cell. Specifically, the address is written from the address terminal to the non-volatile storage means and used as the address for activating the redundant circuit.
In addition, a control terminal for performing a writing operation of the non-volatile storage means is provided, and a high voltage is applied to the terminal to write information in the non-volatile storage means. In a normal read / write usage state, the redundant circuit is operated only when all the address terminals correspond to the states stored in the nonvolatile storage means.

As the non-volatile storage means, for example, E
A non-volatile memory such as PROM or EEPROM can be used. Further, in a normal MOS transistor, desired control information may be stored by utilizing the shift of the threshold voltage due to the injection of hot carriers. Further, the control information may be permanently stored by an electric fuse that is cut into a desired state by inputting an electric signal from an external terminal.

[0024]

Embodiments of the present invention will now be described in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a conceptual diagram showing an example of a semiconductor device which is an embodiment of the present invention.

The semiconductor device of this embodiment is provided with a plurality of functional blocks 4a and 4b and a plurality of external terminals 2 for accessing these functional blocks 4a and 4b from the outside.

In this case, a function selection block 3 is provided between the plurality of function blocks 4a and 4b and the external terminal 2, and the write control terminal 1 is connected thereto. The write control terminal 1 is provided, together with the external terminal 2, for example, protruding from the outside of a package that seals a semiconductor element body (not shown) in which the functional blocks 4a and 4b are formed.

The external terminal 2 naturally includes, for example, a test pad in probe inspection in a wafer state.

The function selection block 3 is composed of, for example, a non-volatile element, and selects a signal from the external terminal 2 according to the control information written in the non-volatile element to select a plurality of function blocks 4a and 4b. External terminal 2
The electrical connection between them is changed to activate one of the functional blocks 4a and 4b. Thereby, the function of the semiconductor device can be changed. The write control terminal 1 connected to the function selection block 3 controls the operation of writing control information to the nonvolatile element forming the function selection block 3.

For example, when the write control terminal 1 is set to a specific signal level, a specific signal state applied to the plurality of external terminals 2 is stored, and the external terminal 2 later stores this specific signal. Function block 4
It is conceivable to perform a control operation such as selectively connecting the external terminal 2 to a or 4b.

The function selection block 3 is not limited to a non-volatile element, but may be, for example, an electric fuse or the like capable of controlling the presence or absence of disconnection and the permanent change of electric resistance depending on the level of the applied voltage and the magnitude of the current. You may comprise.

The nonvolatile element is EEPRO.
It is not limited to a structure in which a floating gate is provided in a gate insulating film between a control gate and a channel of a MOS transistor, such as M and EPROM, but a normal MOS
Specific control information may be permanently stored by utilizing the shift of the threshold voltage due to the injection of hot carriers into the gate insulating film of the transistor.

As described above, according to the semiconductor device of this embodiment, by setting desired control information in the function selection block 3 via the external terminal 2 and the write control terminal 1,
For example, the connection state of the plurality of external terminals 2 and the plurality of function blocks 4a and 4b can be arbitrarily set, so that the function can be changed not only during the probe inspection in the wafer state but also after packaging or mounting. can get.

Further, a plurality of functional blocks 4a and 4b are provided.
When one of them has a relationship of compensating for the functional defect of the other, it becomes possible to relieve the functional defect after packaging or after mounting, and the yield of the semiconductor device is improved.

(Embodiment 2) FIG. 2 is a conceptual diagram showing an example of the configuration of a semiconductor device according to another embodiment of the present invention. In the case of the second embodiment, a case where it is applied to a semiconductor memory as an example of a semiconductor device will be described.

The semiconductor memory of this embodiment includes an address terminal 5, a decoder 8, a memory array 9, an I / O control block 12 and an I / O terminal 13.

Further, in the case of the present embodiment, in addition to the above-mentioned configuration, the write control terminal 6, the address storage block 7,
A redundant memory cell decoder 10 and a redundant memory cell 11 capable of substituting at least part of the functions of the memory array 9 are provided.

The address terminal 5 is used for the normal memory array 9
Is connected to a decoder 8 for selecting and an address storage block 7 for storing an address. The address storage block 7 is composed of a non-volatile element, and the memory array 9 is included in the non-volatile element composing the address storage block 7.
Store the address of the bad bit at. A write control terminal 6 is connected to the address storage block 7. The storage of the address in the non-volatile element forming the address storage block 7 is performed by applying the address to the address terminal 5 and using the write control terminal 6.

For example, when the address to be stored is 12, the number is 1100 in binary display. This is made to correspond to the address terminals 5 of A3 to A0, 1 level is applied to the address terminal 5 of A3, and 0 level is applied to the address terminal of A1. The other address terminals similarly apply corresponding levels. In this state, a write level voltage which is not normally applied is applied to the write control terminal 6. With this applied voltage, an address is written in the non-volatile element forming the address storage block 7.

The nonvolatile element is EEPRO.
It is not limited to a structure in which a floating gate is provided in a gate insulating film between a control gate and a channel of a MOS transistor, such as M and EPROM, but a normal MOS
Specific control information may be permanently stored by utilizing the shift of the threshold voltage due to the injection of hot carriers into the gate insulating film of the transistor.

Thus, in the semiconductor memory in which a specific address is written in the address storage block 7, the redundant memory cell decoder 10 is activated and the redundant memory cell 11 is operated only when the written address is input, and the memory array is operated. Instead of the corresponding address area in 9, write and read operations are performed. Further, the redundant memory cell decoder 10 uses the control line 10a for I / O.
Memory array 9 connected to control block 12
Alternatively, the data output from the redundant memory cell 11 is selected. The I / O control block 12 outputs the selected data to the I / O terminal 13.

Further, the write control terminal 6 does not need to be newly provided, and may be used also as a control terminal or a power supply terminal included in an ordinary semiconductor memory.

As described above, according to the semiconductor memory of the present embodiment, even if a defect in the memory array 9 is found after packaging or mounting, for example, the address terminal 5 and the write control terminal 6 cause the memory array 9 in the memory array 9. By substituting the function of the defective portion for the redundant memory cell 11, it becomes possible to fulfill the function of the semiconductor memory as a whole, and the product yield of the semiconductor memory is surely improved.

Further, it becomes possible to greatly simplify the trouble repair work due to the defect in the memory array 9.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

[0046]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

According to the semiconductor device of the present invention, it is possible to select and use an arbitrary function from a plurality of functions after packaging or mounting.

When a plurality of functions are a specific function and a redundant function for performing an alternative operation of the specific function, the defect of the specific function is substituted by the redundant function at any time, so that after packaging or after mounting. It is possible to improve the product yield by repairing the defective portion.

Further, when the semiconductor device is applied to a semiconductor memory having a main memory section and a redundant memory section capable of substituting at least a part of the main memory section, it is applied even after packaging or mounting. By switching the defective portion of the main memory portion to the redundant memory portion, it becomes possible to replace the defective bit with a bit that operates normally, and the yield of the semiconductor memory can be improved.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing an example of a semiconductor device that is an embodiment of the present invention.

FIG. 2 is a conceptual diagram showing an example of a configuration of a semiconductor device which is another embodiment of the present invention.

[Explanation of symbols]

 1 write control terminal 2 external terminal 3 function selection block (nonvolatile storage means: control means) 4a functional block 4b functional block 5 address terminal 6 write control terminal 7 address storage block (nonvolatile storage means) 8 decoder 9 memory array (function Block) 10 redundant memory cell decoder (control means) 10a control line 11 redundant memory cell (functional block) 12 I / O control block 13 I / O terminal

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G11C 29/00 301 B 6866-5L H01L 21/82 27/10 491 7210-4M 8832-4M H01L 21 / 82 A 8832-4MS

Claims (7)

[Claims] 1. A semiconductor device comprising a non-volatile storage means for changing an internal electrical connection state by an electric signal from an external terminal. 2. A plurality of functional blocks and an external terminal provided commonly or independently to the functional blocks,
Non-volatile storage means in which control information is written via the external terminal, and control means for activating any functional block among the plurality of functional blocks by the control information in the non-volatile storage means. Characteristic semiconductor device. 3. The plurality of functional blocks each include a main memory section and a redundant memory section capable of substituting at least a part of the functions of the main memory section, and the external terminals include the main memory section and the redundant section. An address terminal for inputting an address to at least one of the memory units, the non-volatile storage means stores control information input from the address terminal, and the control means is written in the non-volatile storage means. 3. The semiconductor device according to claim 2, wherein an operation for activating the redundant memory section is performed based on the control information. 4. A part of the external terminal functions as a control terminal for controlling writing of information to the nonvolatile storage means via the external terminal. Semiconductor device. 5. The semiconductor device according to claim 1, wherein the non-volatile memory means is composed of a non-volatile memory element. 6. The non-volatile memory means comprises an electric fuse whose state is permanently changed by input of an electric signal from the external terminal.
The semiconductor device according to 2, 3, or 4. 7. The non-volatile storage means is composed of a MOS transistor, and stores information input from the external terminal by utilizing shift of a threshold voltage due to injection of hot carriers. , 2, 3 or 4
The semiconductor device described.